1. Technical Field
The present invention relates to a wire bonding apparatus that performs bonding while causing the capillary to vibrate by means of a piezoelectric element.
2. Description of the Related Art
Japanese Patent No. 3245445 (Japanese Patent Application Laid-Open (Kokai) No. H5-275502) discloses an example of a wire bonding apparatus that causes a capillary to vibrate by means of a piezoelectric element. In this prior art, a piezoelectric element is incorporated in the vicinity of the capillary attachment portion of the bonding arm so that the capillary vibrates in the axial direction of the bonding arm. In the bonding arm, a preparatory pressure bolt that applies a preparatory pressure to the piezoelectric element is installed on the axial line of the bonding arm in the rear portion of or behind the piezoelectric element.
In the above-described prior art, the preparatory pressure bolt that applies a preparatory pressure is provided on the axial line of the bonding arm on the rear portion of or behind the piezoelectric element; accordingly, adjustment of the preparatory pressure and replacement of the piezoelectric element cannot be performed unless the bonding arm is removed from the bonding apparatus, which is inconvenient and leads to the problem of inferior maintenance characteristics.